(Not Applicable)
1. Field of the Invention
This invention relates to theft deterrent devices, and more particularly to hard tags particularly used in electronic article surveillance systems.
2. Description of the Relevant Art
Theft deterrent hard tags are used to protect many articles, including clothing and other soft goods. Usually, the tags include electronic article surveillance structure. This structure signals a receiver electronically when the tag comes within range of the receiver. The receiver is typically located at or near a store exit and signals an alarm if the tag comes within a specified range, typically, 3 feet to 9 feet. The distance depends in part upon the particular electronic article surveillance technology that is used. The tag is normally removed by the cashier at the point of sale, so that the customer can pass near to the receiver with goods which have been purchased, without signaling the receiver.
EAS tags typically utilize a nail-like pin which has a large head. The pin is passed through the cloth or other soft portion of the article, and is engaged to a pin retainer mechanism within the tag. When the pin is fully seated in the retainer, the large pin head holds the cloth to the body of the tag and prevents removal of the tag/pin assembly from the article. The retainer is quite strong and will release the pin only by the cashier or other authorized person using a special tool.
Several different pin and retainer assemblies are known in the art. One such retainer is a clamp which engages locking grooves in the pin when the pin is inserted into the retainer. A mechanical or magnetic tool is used to move the clamp out of engagement with the pin, such that the pin can be removed from the retainer and the tag removed from the article. Other retainer mechanisms include ball clutches and wedge clutches.
Two-part pin and tag mechanisms are not easily or safely handled. The pin presents a hazard when it is removed from the tag. This hazard can be especially acute in a self check-out system in which customers are expected to remove the tags themselves, after paying for the goods using various proposed electronic self check-out systems. It is, therefore, desirable to provide a theft deterrent hard tag which will not present the hazards encountered by current two-part pin and tag mechanisms.
Current pins are approximately 0.047 inches in diameter with circular locking grooves. This structure is detrimental when tagging finely woven cloth because the large pin size creates a large hole in the cloth, and can snag the cloth on the grooves which are provided on the pin to engage the retainer. Magnetically releasable clutches are desirable retainers because they do not damage the pin and are relatively simple to use. Magnetically releasable clutches can sometimes be compromised, however, by using a strong magnet or by striking on a hard surface. These techniques can be used to release the magnetically releasable clutch from locking engagement with the grooves on the pin shaft. There is accordingly a need for a magnetic clutch that is more difficult to defeat than prior magnetic clutch devices.
The invention provides a theft deterrent device with a tag having a body portion and an attachment portion. The attachment portion has an upper jaw and a lower jaw. The upper jaw is spaced from the lower jaw so as to define a mouth into which a portion of an article can be inserted. A pin is movably mounted in the upper jaw, at least between a retracted position in which the pin does not substantially extend into the mouth, and an extended position in which the pin extends through the mouth and into the lower jaw. Releasable locking structure is provided to secure the pin in the extended position.
The releasable locking structure can be provided in the upper jaw, in the lower jaw, or both. The provision of more than one locking structure makes the theft deterrent device more difficult to compromise. The releasable locking structure can comprise any suitable structure, such as clamp and clutch mechanisms. Magnetically releasable structure is preferred. If the locking structure is a magnetically releasable locking structure, then more than one locking structure is preferred because magnetic locking structures can be compromised by striking the device against a hard surface, or by placing a single strong magnet adjacent to the locking structure. The magnetically releasable locking structure preferably comprises at least one spring catch. The spring catch has a first position in which the spring catch locks the pin in the extended position. The spring catch is movable by the positioning of at least one magnet substantially adjacent to the spring catch to a second position in which the spring catch permits the pin to return to the retracted position. The releasable locking structure preferably includes at least two spring catches, such that at least two magnets, one positioned substantially adjacent to each spring catch, are necessary to permit the pin to return to the retracted position. The pin preferably has a point at one end, and an opposite end that is secured to a head. The head is movably mounted in a chamber in the upper jaw, but is not completely removable from the chamber. Pushing on the head moves the head in the chamber and thereby moves the pin to the extended position.
Biasing structure is preferably provided for returning the head and the pin to the retracted position. The biasing structure preferably comprises at least one compression spring provided in the chamber and acting between the head and a base of the chamber. At least two spring catches are preferably provided in the chamber. The head can have locking tabs for engaging the spring catches, whereby the spring catches must be acted upon by magnets to move the spring catches out of locking engagement with the locking tabs.
A foot can be movably mounted in an aperture in the base of the chamber. The foot has a channel for receiving the pin. Structure operatively connects the foot to the head, such that movement of the head moves the foot through the aperture and into the mouth so as to engage the article while the pin pierces the article. The structure for operatively connecting the foot to the head preferably comprises at least one compression spring mounted between the foot and the head. When the head is moved to the extended position, the compression spring will bias the foot into engagement with the article. The foot, when extended into the mouth, will engage the article around the pin, pressing the article against the upper surface of the lower jaw, thus helping to prevent tearing of the article by movement against the pin. Biasing structure is preferably also provided for biasing the foot into the chamber. The biasing structure will return the foot into the chamber when the head returns to the retracted position.
The body portion of the tag preferably includes structure for signaling an electronic article surveillance receiver, and/or a radio frequency identification (RFID) device.